1. Field of the Invention
The present invention generally relates to disk apparatuses, and particularly relates to a disk apparatus provided with a carriage arm that has a head slider at the tip thereof and are supported by a chassis so as to be able to swing.
2. Description of the Related Art
Hard-drives that magnetically store information therein are typically used as built-in components inside computers. Notebook-type portable computers often suffer impact when they are accidentally hit or dropped. Hard-drives provided as built-in components inside the notebook-type computers are therefore required to have a structure that is more robust against impact than the hard-drives provided in desktop-type computers.
The hard-drives that are built-in components of notebook-type computers employ a ramp-load scheme in which a head slider is evacuated out of the disk space when the hard-drive comes to a halt, thereby improving an anti-impact performance. In addition, an inertia latch mechanism is employed that operates when relatively great impact is applied in a direction in which the carriage arm moves. The inertia latch latches the carriage arm so as to prevent the rotation thereof, thereby preventing the head slider from jumping on to the halted disk and sliding thereon to destroy data recorded in the disk.
The inertia latch mechanism needs to operate reliably when there is impact, and also needs to release the carriage arm reliably thereafter. If releasing is not complete, the carriage arm cannot swing when a load command is supplied, resulting in a malfunction of the hard-drive.
FIGS. 1A and 1B are illustrative drawings showing a related-art inertia latch mechanism that is provided in a hard-drive. A chassis base 10, a cover 11, and a latch arm 12 for latching a carriage arm are shown. The latch arm 12 has a bearing 12a thereof that engages in a fixed axis 13 standing on the chassis base 10, so that the latch arm 12 can swing around the fixed axis 13.
The latch arm 12 is attracted by a magnetic flux leaking from a magnetic circuit of the actuator so as to stay at a latch release position. When relatively great impact is applied, the latch arm 12 swings and reaches a latch position where it latches the carriage arm, thereby preventing the carriage arm from rotating. When an impact force dissipates, the latch arm 12 is attracted by the magnetic flux again to return to its original position.
The bearing 12a of the latch arm 12 has circular flat surfaces 12a1 and 12a2 on the lower and upper ends thereof, respectively. The circular flat surface 12a1 is placed upon a circular flat surface 13a1 of a flange portion 13a of the fixed axis 13. In this manner, the bearing 12a of the latch arm 12 maintains a surface-to-surface contact with the flange portion 13a of the fixed axis 13. The latch arm 12 swings by sliding, overcoming the resistance caused by friction of the surface contact. The circular flat surface 12a1 of the latch arm 12 and the circular flat surface 13a1 of the flange portion 13a have relatively large friction caused by the surface contact. This may undesirably prevent smooth rotation of the latch arm 12.
If the rotation of the latch arm 12 returning to its original position after the dissipation of an impacting force is not complete, the releasing of the carriage arm by the latch ends up being incomplete. This results in the carriage arm failing to swing when a load command is supplied, thereby causing a malfunction of the hard-drive.
It is a general object of the present invention to provide a disk apparatus that substantially obviates one or more of the problems caused by the limitations and disadvantages of the related art.
Features and advantages of the present invention will be set forth in the description which follows, and in part will become apparent from the description and the accompanying drawings, or may be learned by practice of the invention according to the teachings provided in the description. Objects as well as other features and advantages of the present invention will be realized and attained by a disk apparatus particularly pointed out in the specification in such full, clear, concise, and exact terms as to enable a person having ordinary skill in the art to practice the invention.
To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, a disk apparatus according to the present invention includes a disk in which information is recorded, a carriage arm having a head slider provided at a tip thereof, the head slider moving over the disk during a read/write operation and being placed at an evacuated position outside an area of the disk during a halt of the disk apparatus, a support base, and a inertia latch mechanism which slides on the support base from an original position to a latch position in response to an impacting force so as to latch the carriage arm when the disk apparatus is impacted, and slides on the support base from the latch position to the original position by disengaging from the carriage arm after dissipation of the impacting force, wherein the support base and the inertia latch mechanism are in contact with each other through at least one raised portion that prevents a single surface-to-surface contact from being dominant between the support base and the inertia latch mechanism.
The raised portion or portions prevent a single surface-to-surface contact from being dominant between the support base and the inertia latch mechanism by establishing a point contact, a line contact, or a plurality of discontinuous surface contacts, thereby reducing an area of contact between the inertia latch mechanism and the support base. This reduces slide friction, and facilitates smooth sliding movement, thereby improving the reliability of an inertia latch mechanism.
According to another aspect of the present invention, a disk apparatus includes a disk in which information is recorded, a carriage arm having a head slider provided at a tip thereof, the head slider moving over the disk during a read/write operation and being placed at an evacuated position outside an area of the disk during a halt of the disk apparatus, a magnetic circuit which drives the carriage arm, a support base, and a inertia latch mechanism which slides on the support base from an original position to a latch position in response to an impacting force so as to latch the carriage arm when the disk apparatus is impacted, and slides on the support base from the latch position to the original position in response to an attraction force by disengaging from the carriage arm after dissipation of the impacting force, the inertia latch mechanism including a portion thereof made of a synthetic resin mixed with metal particles that respond to magnetism generated by the magnetic circuit so as to generate the attraction force.
In the disk apparatus described above, a portion of the inertia latch mechanism is made of a synthetic resin mixed with metal particles, and can thus be molded into any desired shape and size with sufficient accuracy. Use of this portion makes it possible to arrange mechanical parts accurately, so that a gap between this portion and the magnetic circuit can be made small, thereby increasing the force by which the magnetic circuit attracts the inertia latch mechanism.
Other objects and further features of the present invention will be apparent from the following detailed description when read in conjunction with the accompanying drawings.